/**
 * rem
 */
(function(doc, win) {
    var docEl = doc.documentElement,
    resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',
    recalc = function() {
        var clientWidth = docEl.clientWidth
        if (!clientWidth) return
        docEl.style.fontSize = 100.00 * (clientWidth / 1920) + 'px'
    }
    if (!doc.addEventListener) return
    win.addEventListener(resizeEvt, recalc, false)
    doc.addEventListener('DOMContentLoaded', recalc, false)
})(document, window)